有机碳分布对氮素迁移转化的影响数值模拟  

Numerical Simulation of Soil Water and Nitrogen Dynamics Impacted by Input Organic Carbon

作　　者：刘琨[1] 朱焱[1] 王丽影[2] 程先军[3] 杨金忠[1] 史良胜[1] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,武汉430072 [2]中水珠江规划勘测设计有限公司,广州510610 [3]中国水利水电科学研究院水利研究所,北京100048

出　　处：《中国农村水利水电》2016年第8期52-58,共7页China Rural Water and Hydropower

基　　金：国家自然科学基金青年基金项目(51409192)

摘　　要：针对外源性有机碳影响下土壤氮素各转化过程的定量计算问题,基于土壤氮素迁移转化数值模型NPTTM,考虑外源性有机碳在土壤中的不同分布类型,及其对反硝化过程的影响函数,采用含有机碳的二级处理再生水灌溉试验对该改进模型进行验证,结果表明,改进后的模型能很好地拟合试验过程土壤水氮动态变化过程。同时,为了探究有机碳分布对氮素迁移转化过程的影响,本文采用该验证模型进行有机碳随深度分配数值实验,计算结果表明不同的有机碳分布对土壤铵态氮的影响较小,但对硝态氮的影响较大。土壤中较高的有机碳汇集会造成铵态氮浓度的增加,而有机碳浓度增大会增强反硝化作用进而减小硝态氮浓度。The soil water and nitrogen transformation and transport model NPTTM has been improved to evaluate the impact of input organic carbon on the nitrogen transformation processes quantitatively. Different organic carbon distribution types have been consid- ered, and the impact function of organic carbon on denitrification was added in the model code. Then the modified NPTTM model was adopted to simulate the soil water and nitrogen （including nitrate and ammonium） dynamics under the secondary reclaimed sew- age irrigation. The results showed good agreements between the simulations and measurements. Furthermore, the impact of four or- ganic carbon distribution functions have been investigated by the modified model with the validated parameters. It shows that the or ganic carbon distribution types have slight impact on the ammonium concentration in the soil, while they can affect the nitrate trans- port and fate significantly. Higher organic carbon concentration contributes to the increasing of ammonium concentration. However, high organic carbon concentration leads to lower nitrate concentration because of stronger denitrification reaction rate.

关 键 词：再生水灌溉 改进的NPTTM模型 有机碳分布 氮素迁移转化 

分 类 号：TV93[水利工程—水利水电工程] S27[农业科学—农业水土工程]